app_launcher: Update list of apps on Active User change.

Test: Manually
Bug: 836266
Change-Id: I90ffbc6222d0af85c307eda29974156e9ff314bd
Reviewed-on: https://chromium-review.googlesource.com/1043485Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#556099}

chrome/browser/ui/app_list/app_list_client_impl.cc

@@ -49,9 +49,13 @@ AppListClientImpl::AppListClientImpl()
 
   AppListServiceImpl::GetInstance()->SetAppListControllerAndClient(
       app_list_controller_.get(), this);
+
+  user_manager::UserManager::Get()->AddSessionStateObserver(this);
 }
 
-AppListClientImpl::~AppListClientImpl() = default;
+AppListClientImpl::~AppListClientImpl() {
+  user_manager::UserManager::Get()->RemoveSessionStateObserver(this);
+}
 
 void AppListClientImpl::StartSearch(const base::string16& raw_query) {
   if (search_controller_) {
@@ -188,6 +192,13 @@ void AppListClientImpl::OnItemUpdated(ash::mojom::AppListItemMetadataPtr item) {
   model_updater_->OnItemUpdated(std::move(item));
 }
 
+void AppListClientImpl::ActiveUserChanged(
+    const user_manager::User* active_user) {
+  if (!active_user->is_profile_created())
+    return;
+  UpdateProfile();
+}
+
 void AppListClientImpl::UpdateProfile() {
   Profile* profile = ProfileManager::GetActiveUserProfile();
   app_list::AppListSyncableService* syncable_service =
@@ -223,12 +234,12 @@ void AppListClientImpl::SetProfile(Profile* new_profile) {
   DCHECK(!profile_->IsGuestSession() || profile_->IsOffTheRecord())
       << "Guest mode must use incognito profile";
 
-  TemplateURLService* template_url_service =
-      TemplateURLServiceFactory::GetForProfile(profile_);
-  template_url_service_observer_.Add(template_url_service);
+  template_url_service_observer_.Add(
+      TemplateURLServiceFactory::GetForProfile(profile_));
 
   app_list::AppListSyncableService* syncable_service =
       app_list::AppListSyncableServiceFactory::GetForProfile(profile_);
+
   model_updater_ = syncable_service->GetModelUpdater();
   model_updater_->SetActive(true);
 

chrome/browser/ui/app_list/app_list_client_impl.h

@@ -17,6 +17,7 @@
 #include "base/scoped_observer.h"
 #include "components/search_engines/template_url_service.h"
 #include "components/search_engines/template_url_service_observer.h"
+#include "components/user_manager/user_manager.h"
 #include "mojo/public/cpp/bindings/associated_binding.h"
 #include "mojo/public/cpp/bindings/binding.h"
 
@@ -30,8 +31,10 @@ class AppListModelUpdater;
 class AppSyncUIStateWatcher;
 class Profile;
 
-class AppListClientImpl : public ash::mojom::AppListClient,
-                          public TemplateURLServiceObserver {
+class AppListClientImpl
+    : public ash::mojom::AppListClient,
+      public user_manager::UserManager::UserSessionStateObserver,
+      public TemplateURLServiceObserver {
  public:
   AppListClientImpl();
   ~AppListClientImpl() override;
@@ -63,8 +66,11 @@ class AppListClientImpl : public ash::mojom::AppListClient,
   void OnFolderDeleted(ash::mojom::AppListItemMetadataPtr item) override;
   void OnItemUpdated(ash::mojom::AppListItemMetadataPtr item) override;
 
+  // user_manager::UserManager::UserSessionStateObserver:
+  void ActiveUserChanged(const user_manager::User* active_user) override;
+
   // Associates this client with the current active user, called when this
-  // client is accessed.
+  // client is accessed or active user is changed.
   void UpdateProfile();
 
   void set_controller_delegate(AppListControllerDelegate* controller_delegate) {